Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
so sanh » do sanh
sanh ky » hanh ky, sang ky, nganh ky
lang xa » dang xay, lang van
lang ha » long ha
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
va hanh » van hanh, va thanh, va danh
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh ky ((lang xa) OR (lang ha)) hoi. hieu va cac duc va hanh dai ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh ky ((lang xa) or (lang ha)) hoi. hieu va cac duc va hanh dai ((cua tre) OR (cua te))~".
• Adding a wildcard symbol may retrieve word variants: so sanh ky ((lang xa) or (lang ha)) hoi. hieu va cac duc va hanh dai ((cua tre) OR (cua te))*.